2026/05/21 by Yinyu Yan, Yichao Sun, Carlos A. Teixeira +5
Engineering · #Electromagnetic Compatibility and Noise Suppression #Full-Duplex Wireless Communications #Advanced Power Amplifier Design
paper · doi:10.1109/tpel.2026.3695878
The modular multilevel converter-based solid-state transformer (MMC-SST), containing a dual active bridge (DAB) converter connected to each individual submodule, presents high cost because of its large number of switching devices. A novel integrated switch pairs-based MMC-SST (ISP-MMC-SST) is proposed in this work, where a switch pair (i.e., half-bridge) in each submodule serves as both the conventional MMC submodule and half of the primary-stage of the DAB converter. This approach reduces the switching devices count by 47% compared to the traditional DAB-type MMC-SST and achieves a significant reduction of the SST cost. A hybrid-frequency modulation strategy that enables soft switching of the primary- and secondary-side switching devices using the superposition of carrier-frequency square-wave modulation signals to the fundamental-frequency modulation commands is also proposed. The superimposed square-wave modulation signals are arranged as differential-mode terms across the primary-side switching pairs to deliver power to the secondary side. The proposed topology, hybrid-frequency modulation, and mapping of soft-switching regions for various operating scenarios are validated using industry-scale converter simulations and experiments on a laboratory-scale converter prototype.